International patent application WO 2004/069017 discloses an ice cream scoop comprising a rigid annular frame and a bottom in the form of a cap made of a flexible material. The ice cream contained in the scoop can be expelled by deforming the flexible bottom with a finger.
Application EP 1 371 314 A1 describes a scoop of structure analogous to that described in application WO 2004/069017, together with a lever acting on the flexible bottom.
Application EP 1 516 539 A1 also discloses an ice cream scoop comprising two elements that are pivotally mounted relative to each other, a spring being interposed between the two elements to space them apart. One of the elements includes a frame at one end, and the other element includes a cup designed to co-operate with the frame to form a cavity for taking ice cream.
Each of U.S. Pat. Nos. 4,392,806, 2,756,698, and 4,161,381 discloses an ice cream scoop comprising a cup provided with a bottom tongue of rounded shape and capable of pivoting to expel the ice cream.                U.S. Pat. No. 2,660,784 describes a measuring scoop having a portion-taking cavity with a pivoting tongue in the bottom thereof. The tongue is provided with a spring-forming portion and it serves to expel the substance.        
U.S. Pat. No. 6,162,039 describes a device for taking a portion of a foodstuff, the device comprising a scoop with a plate placed in the bottom thereof to expel its content.
Patent application US 2005/160807 describes a device having a handle and a measuring scoop including a portion-taking cavity having, in its bottom, a plate that is capable of pivoting under the action of a pressbutton situated on the handle.
Patent application JP 07 286885 describes a scoop having a structure close to that described in application US 2005/160807. It describes two variants: in the first variant, the user turns an element on the handle that is also secured to the bottom of the cavity; in the second variant the user moves a pushbutton on the handle, thereby driving a belt that exerts thrust on the bottom of the cavity.
Patent application DE 197 36 078 describes a measuring device comprising a measuring receptacle and a side wall that is movable relative to the measuring receptacle.
U.S. Pat. No. 6,408,521 describes a device for taking a foodstuff, the device having a scoop at one of its ends and a measuring scoop at each other end. The foodstuff can travel inside the handle from one end of the device to the other.
Known devices for taking and extracting a ball of ice cream are not necessarily suitable for non-food substances of different consistency and stickiness, and in addition they do not set out to measure accurately. Furthermore, at least some of those devices can be a relatively expensive to make.
Also, in the field of hair-care products, and in particular for coloring or bleaching, bleaching pastes, in particular those obtained by high-pressure extrusion, are occupying an increasing market share, replacing formulations that are more liquid.
These pastes, which are normally used mixed with a developer in predefined proportions, can present consistency that is quite firm, with a tendency to adhere easily to the walls of scoops used for taking them, which is harmful for measurement accuracy and complicates the mixing operation.